1. Field of the Invention
The present invention relates to a mirror device with an antenna in which the antenna (for example, a giga hertz band antenna including such a satellite broadcasting receiving antenna for receiving an XM radio and a mobile broadcasting in the mirror device of a vehicle) is built.
2. Description of the Related Art
Conventionally, it is common to place a giga hertz band antenna (hereinafter referred to as antenna) used in such a satellite broadcasting receiving antenna on a roof of a vehicle or a trunk assumed to be best in performance. However, if placing the antenna on such a roof of a vehicle as above, there is a trouble that an appearance of the vehicle becomes worse because the antenna and a cable therefor can be seen by a user. In addition, if placing the antenna on such a roof of a vehicle, there is also a problem that a sound of cutting wind occurs in running. Consequently, in order to solve such the problems is recently suggested a method of storing an antenna inside a door mirror of a vehicle (for example, Japanese Patent Laid-Open Publication Nos. H 9-246827 (paragraphs 0017 and 0018, and FIG. 1), 2004-168153 (paragraphs 0014 and 0019, and FIG. 1), and 2004-130875 (paragraphs 0014 to 0016 and 0022, and FIG. 1).
In this connection, in vehicle door mirror devices described in the three patents, in order to ground an antenna housed in a mirror housing (door mirror case), a grounding cable from the antenna is pulled all the way from within the mirror housing to outside and is connected to a door or a mirror base (door mirror stay). Therefore, a work of pulling the cable all the way in assembling a vehicle becomes a troublesome work, and there exists a problem that a workability lowers.
In addition, because a through hole cannot but be drilled through such a mirror housing and a mirror base in order to pull a grounding cable all the way from the mirror housing to outside, there also exists a problem that not only a structure of a vehicle door mirror device becomes complicated but also manufacturing cost becomes expensive.
Consequently, a mirror device with an antenna is strongly requested that can make it unnecessary or simple a work of pulling a grounding cable all the way from a mirror housing to outside in order to ground the antenna, improve a workability in assembling a vehicle, and simplify a whole structure and suppress manufacturing cost cheaper.